Field of the Invention
The present invention concerns an operating method for a computer, that receives information about a measurement sequence to be implemented by a medical imaging system, wherein the measurement sequence includes a predetermined number of successive partial sequences, and wherein the execution of the partial sequences leads to a loading (stressing) of at least one component of the imaging medical technology system.
The present invention furthermore concerns a non-transitory computer-readable storage medium that includes machine code that can be executed directly by a computer, in order to cause the computer to be operated according to an operating method of the above type.
The present invention furthermore concerns a computer at which is stored such a computer program executable by the computer.
The present invention furthermore concerns a medical imaging system that has at least one component that is loaded by operation of the system with a measurement sequence composed of a predetermined number of partial sequences, and that has a control device designed as a computer of the type described above, or is connected with such a computer.
Description of the Prior Art
Methods, systems and computers of the above type are described in DE 10 2008 015 261 B4 and the corresponding US 2009/0 240 379 A1, for example.
In such known operating methods, using a model of the medical imaging system, a computer checks whether a resulting loading of the component of the medical imaging system remains below a load limit during the control of the medical imaging system with the measurement sequence. If yes, the computer retains the measurement sequence without modification. If no, the computer inserts a pause between two partial sequences that are in immediate succession.
The known operating method leads to good results if a partial sequence can be executed at any time, in principle. In some cases, however, the partial sequences must be executed in a number of measurement periods, with the measurement periods split into a measurement interval and a pause interval. In such cases, partial sequences can be executed only during the measurement intervals. In such cases, the known procedure does not always lead to optimal results. This is explained in detail in the following using an example.
It is assumed that a medical imaging system should be operated with a number of partial sequences, for example with 300 partial sequences. Each partial sequence requires 200 ms for its execution. An execution of the partial sequences one immediately after another (thus without pause between the individual partial sequences) leads to an impermissibly high loading of a component of the medical imaging system. By contrast, the loading remains within permissible bounds if a pause of 100 ms is respectively introduced between the partial sequences. Furthermore, it is assumed that the measurement sequence should be applied to a living examination subject, with applications of the partial sequences being executed only in phases in which a slight breathing-dependent movement occurs—for example only during breathing pauses or exhalation phases of the examination subject. A breathing period (=measurement period) amounts to 4 s, which is divided in equal parts into an exhalation or breath-hold phase (=measurement interval) and an inhalation or deep breathing phase (=pause interval).
In such a case, seven respective partial intervals can be assembled into a partial sequence group according to the procedure of the prior art. In this case, the duration of the partial sequence groups amounts to7×200 ms+6×100 ms=2000 ms=2 s.
For 300 partial sequences in total, 300/7=43 partial sequence groups must thus be formed. The total duration for execution of the entire measurement sequence thus amounts to 43×4 s=172 s.
In the division of the measurement sequence into the individual partial sequence groups, in the prior art, no consideration is given to the fact that a pause interval (in the form of an inhalation or deep breathing phase) is inevitably present between each of the individual partial sequence groups. In some cases, it can be sufficient (or at least beneficial) to use the pause intervals in order to execute more partial sequences in the measurement intervals, and thus to reduce the number of measurement periods. This is also explained in detail in the following using an example.
Based on the above example, it is additionally assumed that the loading of the component of the medical imaging system remains within allowable bounds even if a pause of 10×100 ms=1000 ms=1 s is respectively introduced after ten respective partial sequences. In such a case, ten partial sequences can be combined into one partial sequence group. In this case, the duration of the partial sequence groups amounts to10×200 ms=2000 ms=2 s.
Nevertheless, the loading of the component of the medical imaging system remains within permissible bounds because a pause interval (=inhalation or deep breathing phase) respectively follows after the execution of the respective partial sequence group, which pause interval—with its duration of 2 s—exceeds the required minimum length of 1 s. For 300 partial sequences in total, it is no longer 43 partial sequence groups, but rather only 300/10=30 partial sequence groups that must be formed. The total duration for execution of the entire measurement sequence thus amounts to 30×4 s=120 s.